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So Time Machine requires you to format your external HD to use it.
- Thread starter lateralus1082
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So is ZFS not used in Leopard as of yet? If I can, I'll use ZFS. But yes, you probably will need to reformat it.
well, that's a no go. I need this external with my Windows partition
Im curious about something, for your situation. Is it possible to partition a drive in half, leave 1 partition fat32 but format the other HFS? If so, you could move everything off that drive onto your main drive (provided you have enough free space), partition the external drive in two, format one side fat32 and the other HFS for TM.
There's no reason why this shouldn't be possible. Just make sure you do the formatting/partitioning in Disk Utility
should work as the OS would see each partition as a seperate drive and you just pick the one you want to back up to. unless it has a built in size limitation (requirement) which would suck.
It seems to support networked AFP shares. I'll have to give it a try with one of my Infrant NAS boxes.
Why it needs the right formatting
Time Machine uses a Unix-style filesystem because of the filesystem feature called "hard links." Using hard links, it can keep multiple snapshots of your files without having to store a file multiple times if it hasn't changed. Only a single copy of a given version of a given file is stored. If the file hasn't changed when a new snapshot is taken, Time Machine stores only a few-byte "hard link" to the original file. So the design of Time Machine depends on having the correct type of filesystem.
Time Machine uses a Unix-style filesystem because of the filesystem feature called "hard links." Using hard links, it can keep multiple snapshots of your files without having to store a file multiple times if it hasn't changed. Only a single copy of a given version of a given file is stored. If the file hasn't changed when a new snapshot is taken, Time Machine stores only a few-byte "hard link" to the original file. So the design of Time Machine depends on having the correct type of filesystem.
So, a stupid question (I ask because I've seen a lot of conflicting info on TM's "picky" nature)… if I want to use TM to backup to a 2-disk RAID 1 array, will it be mirrored correctly?
I assume as much, and have no reason not to expect it to work, but assuming has gotten me into trouble before.
Another question… if I delete a file from my primary HD that I no longer want TM to keep archived, would going back to the very first instance of the file via TM and deleting it remove it from all successive backups? Or is that not how teh hardlinking works.
I assume as much, and have no reason not to expect it to work, but assuming has gotten me into trouble before.
Another question… if I delete a file from my primary HD that I no longer want TM to keep archived, would going back to the very first instance of the file via TM and deleting it remove it from all successive backups? Or is that not how teh hardlinking works.
ZFS is included as Read-Only. Developers have access to Read-Write, but Time Machine does not support it. Also, even if you get Read-Write support, there is no GUI for partitioning / initializing a ZFS, and it's pretty complicated to do it on the command line.
Erasing the oldest copy on the backup disk would not remove it from successive backups. When you delete one hard linked file, the others remain.
More gory details: The data of the file is stored in one place on the hard drive. The directory information (primariliy the path, filename, and a pointer to the data's location) is stored once for each hard link. There really isn't a primary copy and secondary copies; they are all equal -- one file known by multiple names or under multiple paths. The filesystem keeps track of the number of hard links to the file's data. As long as any hard links remain, the data is retained. If you delete the very last remaining hard link to the file, the file's data is finally freed (although it may not actually be overwritten until other data is stored on the drive and happens to land in the same place).
Therefore, to remove all copies of a file, you'd have to find all copies on the backup disk and delete them all. I have yet to confirm this, but I think you won't actually find the file in every snapshot, because if nothing in its enclosing folder has changed between snapshots, only the folder will be hard-linked, not the individual files.
Be sure to read the Time Machine FAQ for lots of other information about Time Machine.
I'm interested to see how this turns out. I thought the website read that it has to be a network share on another Mac running Leopard. If this works with a NAS system, that would make me very happy since I'm in the market right now.
Let me know how it goes.
Thanks.
it is possible...I have the exact same setup you described because I have to use windows occasionally and all my friends use pcs.
byakuya